Backbone.Router extension with "cascade" routing. [WARNING: has some problems because the routes cannot be removed!]

router.js

define(function(require, exports, module) {
  "use strict";

  var Backbone = require("backbone"),
      _ = require("underscore");

  /* The extractor determines the order of the cascading */
  /* shift = bottom first */
  var extractor = "shift";
  /* pop = top first  */
  // var extractor = "pop";

  Backbone.history.loadUrl = function(fragment) {
    fragment = this.fragment = this.getFragment(fragment);
    var middleware = _.filter(this.handlers, function(handler) {
      return handler.route.test(fragment);
    });
    (function handleNext() {
      var handler = middleware[extractor](),
          args = [].slice.call(arguments);
      if (handler) handler.callback.call(this, {next: handleNext, fragment: fragment, params: args});
    })();
  };

  module.exports = Backbone.Router.extend({
    _extractParameters: function(route, info) {
      var urlParams = module.exports.__super__._extractParameters
          .call(this, route, info.fragment).slice(0, -1);
      return [info.next].concat(urlParams).concat(info.params);
    }
  });

});